Auditor-General Michael Ferguson says in his bombshell report this week that the Conservative government knew the F-35 attack jets would cost at least $10 billion more than they were telling the public, says.

Was Harper simply "misinformed" as they say in the movies, or did he give out the wrong figures deliberately to mislead Parliament?

The real cost of Harper's attack jets were $25 billion, Ferguson says in his report. But all through the election campaign and afterwards Harper kept saying they were only $15 billion and there was nothing to worry about.

Ferguson won't go as far as saying Harper lied, only that he was not accurate.

But Thursday in the Commons the Opposition MPs didn't hesitate to accuse Harper of deliberately "misleading" Parliament, which is a most serious thing to do.

Liberal leader Bob Rae called for Harper's resignation. NDP leader and Opposition leader Thomas Mulcair wouldn't go quite as far. He said Parliament has to get to the bottom of what happened.

And as for Harper, he refuses to say why his information was wrong, or when he was told the $15 billion figure. Or who told him.

Harper keeps saying that because they haven't paid the bill for the jets yet, it doesn't really matter what he has been saying. No money, no problem.

New Democrat defence critic Matthew Kellway sees it otherwise: "What's being uncovered here is political rot at the core of the government."

Liberal leader Bob Rae demanded:

"When did the prime minister find out the true cost?"

Harper never answered.

Rae replied: "I don't think this man is fit to be prime minister."

Mulcair took a more legalistic approach: "This is a unique case because now we have clear and convincing evidence that the government provided false information to Parliament. And that's serious!"

A few minutes later Parliament went on a two-week Easter vacation, with Harper hoping the crisis will have died down by the time he gets back.

But there is a problem. U.S. Defence secretary Leon Panetta is saying this week that the cost of the U.S.-made F-35 jets has doubled again.

It should be interesting to find out which figures Harper will be using when he gets back from vacation.